To ping the entire internet in 10 hours you would generate approximately 60 Mbps of ICMP traffic.

The site is down for me, but I assume they used multiple machines to do this. I SYN scanned about 70% of the globally routed prefixes last month and it took a little over 4 days from a single box (but I was doing some detailed packet captures that hurt disk IO).

It took only 10 hours on a single server, more info here: http://www.securityartwork.es/2013/01/21/how-much-does-it-ta...